Address known-broken ChainRules tests

[iajzenszmi]

     Testing Running tests...
Test Summary: | Pass  Total   Time
bessel        |  584    584  21.6s
Test Summary: | Pass  Total   Time
beta_inc      |  943    943  27.8s
Test Summary: | Pass  Total  Time
betanc        |   25     25  0.2s
Test Summary: | Pass  Total  Time
ellip         |   36     36  0.5s
Test Summary: | Pass  Total  Time
erf           |  472    472  2.4s
Test Summary: | Pass  Broken  Total  Time
expint        | 6351       1   6352  9.7s
Test Summary: |    Pass    Total   Time
gamma_inc     | 1001764  1001764  30.6s
Test Summary: | Pass  Total  Time
gamma         |  457    457  4.8s
Test Summary: | Pass  Total  Time
logabsgamma   |   59     59  3.5s
Test Summary: | Pass  Total  Time
sincosint     |   82     82  0.7s
Test Summary: | Pass  Total  Time
other_tests   |  110    110  5.5s
Test Summary: | Pass  Broken  Total     Time
chainrules    | 7381    1476   8857  3m11.8s